1,3,2-oxazaborinides and method for preparing the same

ABSTRACT

COMPOUNDS OF THE FORMULA   2-R,5,5-DI(X-)-OXAZOLO(4&#39;&#39;,5&#39;&#39;:5,6)(1,3,2)OXAZABORINO-   (3,4-A)BENZ(CD)INDOLE   WHEREIN BOTH X&#39;&#39;S ARE THE SAME AND REPRESENT EITHER FLUORO OR ACETOXY AND R REPRESENTSMETHYL, PHENYL OR ACETYLAMINOPHENYL. THESE COMPOUNDS ARE CHARACTERIZED BY AFFINITY FOR POLYESTERS, NYLON AND ACETATE WHEN APPLIED BY DISPERSE DYEING METHODS AND FLUORESCE ON THE FIBER.

United States Patent 3,733,334 1,3,2-OXAZABORINIDES AND METHOD FOR PREPARING THE SAME Thurairaiah Padmanathan, Highland Park, N.J., assignor to American Cyanamid Company, Stamford, Conn. No Drawing. Continuation-impart of application Ser. No.

732,045, May 27, 1968, now Patent No. 3,621,023,

dated Nov. 16, 1971. This application Apr. 19, 1971, Ser. No. 135,361

Int. Cl. C07d 85/36 US. Cl. 260-307 F 2 Claims ABSTRACT OF THE DISCLOSURE Compounds of the formula wherein both Xs are the same and represent either fluoro or acetoxy and R represents methyl, phenyl or acetylaminophenyl. These compounds are characterized by affinity for polyesters, nylon and acetate when applied by disperse dyeing methods and fluoresce on the fiber.

This application is a continuation-in-part of application Ser. No. 732,045, filed May 27, 1968, now Pat. No. 3,621,023.

This invention relates to new heterocyclic compounds containing boron and to certain non-boron intermediates which are outstanding for use as fluorescent disperse dyes. It also relates to a novel method for the preparation of certain of the boron-containing compounds.

Especially this invention relates to 1,3,2-oxazaborinide compounds represented by the formula:

wherein A is the residue of an active ketomethylene compound from which the-l-oxo group is derived, X is halogen or acyloxy; R and R are selected from the group consisting of H, lower alkyl and aryl, individually, or which together with the -NC- group to which they are attached form an azole. These compounds are characterized by their ability to dye synthetic fibers, especially polyester, nylon and acetate, giving mainly yellow to orange to red hues of good fastness to light. The dyed fibers show bright fluorescence in ultraviolet light or yellow to orange to red.

\In practicing this invention, a condensate of the formula represented in a keto and enol form,

(a) H; Hz H1 I ia (b) wherein A, R; and R are defined as above, is reacted with either:

(1) A boron trihalide, such as boron trifluoride or trichloride, in an inert solvent to give a 1,3,2-oxazaborinide represented by the Formula I above, X being fluoro or chloro. The boron trihalide is used in excess. Being gaseous at ordinary temperature it is usually dissolved in an inert organic solvent carrier for addition, such as diethyl ether. It is added to the condensate ab, in a solvent inert to both, such as acetic acid, xylene, chloroform, or nitrobenzene. The reaction is carried out at reflux. The 1,3,2- oxazaborinide is isolated by pouring the reaction mixture on to crushed ice. The separated product is filtered, washed with water and recrystallized from solvents such as chloroform or dimethylformamide, xylene or benzene.

(2) Ortho boric acid, B(OH) or its derivative benzeneboronic acid, Ph B(OH) in acetic acid in the presence of acetic anhydride to give a diacetoxy 1,3,2-oxazaborinide (X=acetoxy). This reaction is also carried out at reflux. The product is insoluble in the cold reaction mixture. Other boronic acids such as benzyl or alkylboronic acids are equally operable. The reaction to give the diacetoxy analogue is unexpected and is an embodiment of this invention, or

(3) The difluoro 1,3,2-oxazaborinide prepared above can serve as a starting material instead of II above for the preparation of the diacetoxy 1,3,2-oxazaborinide.

As starting materials of types II(a) and (b), there may be used condensates formed by reaction of an o-hydroxy aromatic aldehyde with an aromatic amine, exemplified by Example 15. This gives an azomethine compound in which R and R are H, lower alkyl or aryl: e.g.,

Aldehyde o-hydroxybenzaldehyde 2-hydroxy-l-naphthaldehyde Amine mor p-anisidine mor p-phenetidine 1-hydroxy-2-naphthaldehyde 3-hydroxy-2-naphthaldehyde These and their ring-substituted derivatives are known solids. Their preparation is given in the art.

Another class of starting material is type II(a) and (b) above, where R and R form an azole.

One subgeneric type of this class is a 2-(o-hydroxyphenyl)benz-azole such as:

2- o-hydroxyphenyl benzoxazole 2- o-hydroxyphenyl) benzothiazole 2 (o-hydroxyphenyl)benzimidazole These compounds and their ring-substituted derivatives are known in the art as for example US. 2,995,540 and 3,049,509. Their use is described in Examples 12 and 1.3.

Further starting materials of Type II, wherein R and R together form an azole is a peri-naphthazole:

III M salt (IV) such as the hydroidide. IV is condensed with an active ketomethylene compound in alcohol or acetic acid, in the presence of sodium acetate, at reflux for several hours. The product separates, especially on cooling. The active ketomethylene compound may be a pyrazolone (Ex. 1 thru 5), a barbituric acid (Ex. 6 and 7) an indandione (Ex. 8) or a 2-hydroxyindole (Ex. 9, 10). Examples of specific active ketomethylene compounds in addition to those shown in the examples are:

l-(3'-acetylaminophenyl)-3-methyl-2-pyrazolin-S-one 3-anilino-l-phenyl-2-pyrazolin-5-one 3-methyl-1-(2', or 3 or 4'-chlorophenyl)-2-pyrazolin-5- one 3-methyl-l-(2',5-dichlorophenyl)-2-pyrazolin-5-one 3-methyl-l-(4-nitropheny1)-2-pyrazolin-5-one 3-methyl-2-pyrazolin-S-one 3-methyl-l-(2,4,6-trichlorophenyl)-2-pyrazolin-5-one 3-methyl-1-phenyl-2-pyrazolin-5-one 3-methylol-l-phenyl-2-pyrazolin-5-one 3-phenylamino-l-phenyl-2pyrazolin-5-one Direct alkylation or acetylation of the azole nitrogen of the condensation product is difficult. These condensation products are disperse dyes giving orange to brown hues on polyesters with fair to good lightfastness and color value.

Active ketomethylene compounds for practice of this invention are the barbituric acids which are condensed with IV to give products which may be chelated with boron as described above. These include barbituric acid, its N,N-dialkyl and N,N-cyanoalkyl derivatives as listed in the examples, and its N-phenyl derivative. These are condensed in the same way as pyrazolones. Alkylation and cyanoalkylation may be done on the free barbituric acid condensate. The product corresponding to II above may have one, two or three of its nitrogens so substituted. The azole nitrogen is the first one of the three to be substituted. The unchelated condensates are disperse dyes which give bright green-yellow to yellow hues on polyester, nylon, acetate and polyacrylonitrile. They fluoresce bright green-yellow to yellow shades under ultraviolet light. Light-fastness is almost as good as the boron chelates thereof.

Another active ketomethylene compound for the practice of this invention is indandione shown in Example 8. The advantage of this condensate is that it can be halogenated (brominated or chlorinated) or nitrated, to give mono substituents in the six position and disubstituents in the 6,8-positions of the naphthostyril moiety. (See Ring-Index 2935 for numbering.) Or the indandione may be substituted such as 5,6-dibromo or dichloro-1,3-indandione. These are disperse dyes giving yellow to orange hues on polyester, nylon and acetate, and fluoresce on the fiber.

Chelateable condensates may be prepared by condensing IV with glycine or its N-benzoyl or p-aminobenzoyl derivatives. These are acetylated and ring-closed in acetic acid in the presence of acetic anhydride to form azalactones of the type shown in Example 11.

Other chelateable condensates may be formed by condensing IV with active ketomethylene compounds such as 5,5-dimethyl-1,3-cyclohexanedione like those disclosed in column 3 of US. 2,822,359, indoxyl, S-bromo or 5- chloroindoxyl, 2,5-dibromo or 2,5-dichloroindoxyl, 1,8- perinaphth-l,3-indandione, 4 methyl-6,7-benzo-1-thia-5- aza,4,6-cycloheptadiene-2-one, 5-phenyl-6,7-benzo-thia-5- aza,4,6-cycloheptadiene-2-one and the like.

All of the above condensates are chelateable with boron as described. These dihalo and diacyloxy-1,3,2-oxazaborinides have strong affinity for polyester when applied by the method of Example 17 and fluoresce under ultraviolet light. On the fiber they fluoresce yellow to orange to red hues. Many of them are equally intense on nylon and acetate and some on modified polyacrylonitrile. To some ex- 4 tent they dye modified polypropylene but do not fluoresce on this fiber.

A preferred group are the 1,3,2-oxazaborinides derived from naphthostyril and barbituric acid, including its N,N- dialkyl derivatives of l to 4 carbon atoms, N,N-dicyanoethyl and the corresponding thiobarbituric acids. These 1,3,2-oxazaborinides show equally strong affinity and fluorescence on polyester, nylon, acetate and modified polyacrylonitrile having nitrogenous sites such as Creslan Acrylic Fiber, when dyed at the boil.

These dyes seem to have slightly more affinity for polypropylene modified by amides rather than amines. They are not suitable for unmodified polypropylene.

The 1,3,2-oxazaborinides have been represented by Formula I above but could also be represented in four other ways as represented by the following formulas:

A preferred embodiment of this invention is the diacetoxy 1,3,2-oxazaborinide (X =acetoxy) which has been found to be especially stable. This forms in acetic acid in the presence of acetic anhydride. Even when benzeneboronic acid, PhB (OH) is used and the expected product is a monohydroxy monophenyl 1,3,2-oxazaborinide, the phenyl group is not found attached to the boron in the final product. It is split off and the diacetoxy borinide formed instead. The diacetoxy 1,3,2-oxazaborinides are distinct from diphenyl 1,3,2-oxazaborinides of the art because they have greater fluorescence.

Many of the 1,3,2-oxazaborinides of this invention are useful for coloring varnishes, resins and plastics, such as poly(methyl methacrylate), nitrocellulose, polyethylene and polystyrene. They fiuoresce in these substrates, They above is also of commercial interest and their stability to are most useful where intense heat and light are not a factor. Their fluorescence on synthetic fibers as mentioned light on the fiber is good. All of the fibers mentioned may be dyed by the procedure of Example 17.

The following examples illustrate this invention.

EXAMPLE 1 4-benz[cd]indol-2-(1g)-ylidene-3-methyl-1- phenyl-Z-pyrazolin-S-one A mixture of 3.27 g. Z-methylthio-l,2-dihydrobenz[cd]- indole hydriodide IV, hereinafter referred to IV, 1.8 g. 3-methyl-1-phenyl-2-pyrazolin-5-one, and 0.85 g. anhydrous sodium acetate, in ml. ethanol are heated at reflux with stirring for five hours. After cooling, the product is filtered, washed with petroleum ether, dried and recrystallized from mixed ethylene dichloride-ethanol. Yield is 2.0 products, 111. 231-3 C.

EXAMPLE 2 To 2 g. of the product of Example 1 in 100 ml. chloroform heated at reflux, is added ml. boron trifluoride etherate containing 47% BF in ethyl ether. After one hour at reflux, the mixture is diluted with ethanol and poured on to crushed ice. The product is filtered and dried to give 2.1 g. orange crystals melting 27072 C., soluble in chloroform and dimethyl formamide. Recrystallized from dimethyl formamide it melts at 272-74 C.

It dyes polyester a yellow shade of good strength having a F'ade-Ometer lightfastness rating of 4-5. Lighter shades are obtained on nylon, acetate and polypropylene fibers. All fluoresce orange under UV light with the exception of poly propylene.

In general purposes polystyrene in 0.04% concentration, it develops a bright transparent fluorescent orange which shows no significant change after 70 hours exposure in a Fade-Ometer. However, five minutes of heat at 450 F. produces a slight change of shade and strength.

EXAMPLE 3 Dihydroxy 1 methyl 3-phenyl-3g8g-benzyl[3,4] -indolo[ l,2-c]-pyrazolo [4,3 -e] 1,3,2 oxazaborinide diacetate To 2.0 g. product of Example 2 in 30 ml. acetic acid is added 30 ml. acetic anhydride. The whole is heated at reflux until acetoxylation is complete, cooled, the product isolated by filtration and dried. Yield 2.25 g. orange crystals m. 278-80 C., soluble in chloroform. Recrystallization from acetic acid it melts at 28082 C.

This compound dyes polyester, nylon, acetate and polypropylene a burnt orange of good tinctorial strength which fluoresces orange under UV light and has lightfastness rat ings in the range of 4-5. Dyed on polyester in 0.1% shade it is unchanged for 40 hours under Xenon arc lamp.

Instead of the difluoro product of Example 2, the starting material may be the corresponding dichloro 1,3,2- oxazaborinide. The dichloro product is prepared by the procedure of Example 2 except that 2 g. boron trichloride pyridine complex is used instead of the boron trifluoride etherate.

EXAMPLE 4 When 1.0 g. of the compound of Example 1 is heated at reflux with an excess of ortho-boric acid B(OH) 1.0 g. in 35 ml. acetic acid, with 10 acetic anhydride for seven hours, a quanitative yield of the diacetoxy com- If in Example 1, instead of 3-methyl-1-phenyl-2-pyrazolin-S-one, other 2-pyrazolin-5-ones are used in equimolecular amount, and the products reacted with boron trifluoride after the fashion Olf Example 2, corresponding difluoroborinide fluorescent dyes are obtained as follows.

Color on polyester and fluorescence of difiuoro- 2-pyrazolirr5-one borinide derivative 1 B-methyl-L(4'-chlorophenyl) Orange (fluoresces orange). 2. 1,3-diphenyl. Yellow (fluoresces orange). 3-methyl-l-(4nitrophenyl) Orange (bri. orange fluor.). 4 3-carboethoxy-1-phenyl Do.

Dye No. 2 colors poly(methyl methacrylate), ureaformaldehydealkanol and urea-melamine resins yellow which fluoresce yellow under ultraviolet light.

The unchelated precursor of dye No. 4, polyester and acetate reds of good tinctorial strength and lightfastness ratings of 5-6, 5-6 and 6, respectively. The unchelated dye is non-fluorescent. However, when chelated with boron trifluoride, its hue becomes orange and it shows an intense light orange fluorescence on polyester and acetate and to some extent on nylon in UV light.

The diacetoxy 1,3,2-oxazaborinide analogue of No. 2, dyes polyester, nylon, acetate and modified polypropylene o. burnt orange hue which fluoresces alight red-orange on acetate under UV light and to some extent polyester and nylon but not on polypropylene.

EXAMPLE 6 (B) (O) I [j (A) 5-benz[cd]indol-2(1E)-ylidene-barbituric acid To 4.905 g. IV and 1.7 g. sodium acetate in ml. acetic acid at reflux, is added 1.92 g. barbituric acid. Re-

fluxing is continued. When the reaction is complete, the whole is cooled, filtered and the product leached with hot ethanol and washed with acetone, hot ethanol and water. After further washing with hot acetone and warm dimethylformamide the product is dried to give 2.5 g., m. 355-7 C.

The dye is a bright yellow on polyester, nylon, acetate and polyacrylonitrile. Lightfastness rating is respectively 3, 3, -6 and 4.5. Under ultraviolet light, all fibers have a bright light yellow fluorescence. The sodium salt of the dye has similar dyeing properties.

(B) The difluoro borinide Three grams of product (A) in 30 ml. boron trifluoride etherate (of Example 2) are heated at reflux for two hours, cooled and poured into crushed ice. The product is washed with water and dried. Yield is 2.95 g. m. 410- C. of the difluoro borinide compound.

This compound dyes nylon yellow having a lighttfastness rating of 4-5. It fluoresces a bright pale yellow under ultraviolet light. A lower tinctorial eflect and fluorescence is present on the other synthetic fibers.

(C) The diacetoxy borinide To a refluxing mixture of Product A (2.7 g.) in 100 ml. acetic acid is added 1.6 g. ortho-boric acid and ml. acetic anhydride. When the reaction is complete, the whole is cooled and filtered. The product is washed with acetic acid and petroleum ether and dried. Yield 2.75 g., m. 390 C. dec.

The compound dyes nylon, acetate and polyester strong bright green-yellow shades of good fastness to light, rating 4-5, 5-6 and 5, respectively. Under ultraviolet light, the dyed fibers display brilliant green-yellow fluorescence.

EXAMPLE 7 (A) When the product of Example 6(A), is dimethylated to give methyl groups on both nitrogens of the barbituric acid moiety, a product m. 284-86 C. is obtained. It dyes polyester, nylon and acetate bright yellow shades having a lightfastness rating of 3, 4, and 5 respectively. It shows a bright yellow fluorescence on the fibers.

(B) The difluoro borinide of the N,N,-dimethyl derivative prepared as in Example 6(B), m. 335- C., is a similar yellow with especially strong fluorescence on polyester and acetate. Lightfastness is improved respectively to 5-6, 3-4 and 6. This dye can also be dyed on polyester by the Thermosol method.

This product colors poly(methyl methacrylate) resin yellow which under UV light gives a bright light yellow fluorescence.

(C) The diacetoxy borinide derivative prepared as in Example 6(C), 111. 273-5 C., is also a yellow of strong tinctorial value on polyester, nylon and acetate and fair on polypropylene. Lightfastness ratings are 3-4, 3-4, 5-6 and 4, respectively. On these fibers, it fluoresces yellow. It can be dyed on polyester by the Thermosol method.

If N,N-diethyl barbituric acid is used in A, a product m. 284-86 C. is obtained. When converted to the difluoro or diacetoxy borinide, a compound with similar dyeing properties is obtained.

EXAMPLE 8 Diacetoxyand difluoro-14-oxo-8E-benz[3,4]indolo [1,2-c]indeno[2,1-e]-1,3,2-oxazaborinide 0 F omo-ii- B 1+? 13- ou c-o- T T 8 (A) 2-(1,2-dihydro benz[cd]indol-2-ylidene)- 1,3-indandione A mixture of 15.0 g. IV and 3.8 g. sodium acetate is dissolved in 400 ml. hot ethanol. To the solution is added 6.75 g. indan-l,3-dione and heating continued at reflux for six hours. The product is filtered hot, washed with alcohol and dried, m. 287- C. Crystallized from formamide, m. 28991 C.

(B) Difluoro borinide A 5.0 g. sample of A was heated at reflux with ml. boron trifluoride etherate for twenty-four hours, cooled and poured into crushed ice. It was filtered and dried, giving 9.5 g. product. Recrystallized from dimethyl formamide, it melted 304-7 C.

It dyes polyester deep red orange of good color value having better fastness to light than the unchelated (5 to 2-3 respectively). Lighter more yellowish orange shades are obtained on nylon, acetate and modified polyacrylonitrile. However, the latter show a bright pale orange fluorescence under UV light.

When incorporated in thermoplastics such as general purpose polystyrene or poly(methyl mcthacrylate) the color develops well to a bright transparent orange of good lightfastness. 'Its properties in the presence of titanium dioxide are good. It is useful where heat stability is not a factor.

(C) Diacetoxy borinide A mixture of 5.95 g. dye A above, 1.3 g. orthoboric acid, 250 ml. acetic acid and 50 ml. acetic anhydride is heated at reflux for twenty four hours, cooled and the product filtered to give 5.65 g., m. 2978 C.

It dyes polyester acetate and nylon an orange of good color value with a lightfastness of 3 on all fibers. They show an orange fluorescence. It dyes polypropylene an orange which does not fluoresce.

Halogenated and nitrated derivatives of product A like wise are capable of chelation with boron. Examples of these derivatives are the following.

Derivative of A (1) monobromo, m. 315-20 (2) dibromo, 111. 298-300 (3) dichloro, m. 307-10 (4) mononitro, m. 360-5 These dye polyester orange which fluorescence under ultraviolet light. The mono nitro compound has a bright yellow fluorescence under UV light.

EXAMPLE 9 Diacetoxy-8g, 10g benzo[3,4] diindol o[1,2-c:3, 2'-e] 1,3,2-oxazaborinide H 0 l l CHaHl-O B To a refluxing mixture of 1.5 g. of the unchelated dye prepared using the procedure of Example 6(A), with 3-benz[cd]indol-2-yl-indol-2-ol instead of barbituric acid in 75 ml. acetic acid, is added 0.7 g. boric acid and 15 ml. acetic anhydride. After twenty four hours at reflux, the whole is cooled to room temperature, filtered and dried, to give 1.8 g. 310 C. dec.

It dyes polyester, acetate and nylon red shades which fluoresce. The fluorescence on polyester is a strong red under ultraviolet light.

9 EXAMPLE 10 The difluporo borinide corresponding to Example 9 A mixture of 2.0 g. 3-benz[cd]indol-2-yl-indol-2-ol and 30 ml. boron trifluoride etherate having 47% BF is heated at reflux for one and one-half hours, cooled by ice bath and mixed with 25 ml. ethanol. The whole is poured into crushed ice and stirred. The product is filtered washed with ethanol and dried to give 2.1 g., m. 370-75 C.

The product dyes polyester, acetate and nylon, strong red shades. Polyacrylonitrile is dyed a medium red shade. All give a bright coral fluorescence under UV light. Lightfastness is 3-4 on polyacrylonitrile, nylon and acetate, 3 on polyester and 2 on polypropylene.

It colors poly(methyl methacrylate)resin red which fluoresces orange under UV light.

EXAMPLE 11 o ig //o NHCOGHa \B 91+ C-N onaco (A) To a mixture of 6.54 g. IV and 1.65 g. sodium acetate in 50 ml. hot acetic acid is added 3.9 g. N-(paminobenzoyl) glycine dissolved in a mixture of 50 m1. acetic anhydride acid and 25 ml. acetic acid. The whole is heated at reflux for two hours, cooled and drowned in ice. The product is filtered, washed with alcohol and dried to give 3.8 g. product. Recrystallized from dimethylformarnide, it melts 322- C. 'It dyes polyester, nylon, acetate and modified polyacrylonitrile, a bright red hue which under ultraviolet light has a bright red-orange fluorescence.

Without the p-acetylamino group the unchelated dye is a bright red-orange or coral on polyester, fluorescing a very bright orange under UV light. A methyl group instead of phenyl produces a blue-red on polyester which also fluoresces orange.

(B) To a refluxing mixture of 1.5 g. of the unchelated dye prepared in Part A and 75 ml. acetic acid is added 0.7 g. boric acid and 15 ml. acetic anhydride. After 30 minutes at reflux, the whole is cooled to room temperature, filtered and dried. The chelated product dyes polyester, acetate and nylon red-orange shades which fluoresce. The fluorescence on polyester is a strong redorange under ultraviolet light.

EXAMPLE 12 O CHai JO\ OHaCO To 5 g. 2-(o-hydroxyphenyl)-benzothiazole in 50 ml. acetic acid, is added 1.6 g. boric acid and 25 ml. acetic anhydride. The whole is heated at reflux for three hours, cooled, filtered and the product dried. The product is washed with ether and dried to give 5.3 g. m. 25253 C.

This compound has strong aflinity for polyester. Although colorless in daylight, it fluoresces a strong light yellow under ultraviolet light. (It has no aflinity for polyacrylonitrile or wool.) It has some aflinity for acetate and nylon. It fluoresces light yellow on these fibers.

EXAMPLE l3 To 1.0 g. 3-(benzimidazol-2-yl)-2-naphthol discovered by I. L. Rodgers, in 50 ml. acetic acid and 10 ml. acetic anhydride is added 0.28 g. boric acid. The whole is heated at reflux for two and one-half hours, filtered and the product dried; 0.65 g., in. 288 C.

Although colorless on synthetic fibers, it has affinity and fluoresces on them. It has strong aflinity for polyester, fluorescing medium coral shades. On nylon it fluoresces a light orange. For acetate, it has slightly less aflinity and fluorescence.

If in the above procedure the 3-(benzoxazole-2-yl)-2- naphthol is used instead of the imidazole a product of similar substantivity and fluorescence is obtained.

EXAMPLE 14 To 2 g. N-(Z-hydroxy-S-nitrobenzylidene)-p-phenetidine and 1 g. phenylboric acid in 30 m1. acetic acid at reflux, is added 5 ml. acetic anhydride. After heating at reflux for one hour, the whole is cooled and filtered to give 1.0 g. product, in. 240-1 C.

This compound gives light yellow shades on polyester, nylon, acetate and modified polypropylene. However, it is of special interest because of its intense light yellow fluorescence on polyester. The fluorescence is also indicative of the strong affinity this compound has for that fiber.

EXAMPLE 15 The difluoro analogue of the product of Example 14 is prepared as follows:

To a refluxing mixture of 1.0 g. N-(Z-hydroxy-S-nitrobenzylidine)-p-phenetidine in 50 ml. refluxing xylene, is added 1 ml. boron trifluoride etherate (of Example 2). An immediate precipitate forms which dissolves on further refluxing. After three hours at reflux the whole is cooled, filtered and the product dried to give 1.05 g., m. 210-11" C.

The product dyes polyester, nylon and acetate light yellow shades. On polyester it has a light green-yellow fluorescence.

11 EXAMPLE 16 o CHaLO 1 +2 o (3-0 1 NC1 To a solution of 5.22 g. N-(Z-hydroxy-l-naphthylidene)-toluidine in 50 ml. acetic acid is added 2.5 g. phenylboric acid. The whole is heated at reflux for 1.25 hours, cooled and the product filtered, washed with ml. ethanol and dried to give 2.0 g., m. 218-20" C.

If boric acid is used instead of phenylboric acid, the same product is obtained. It dyes polyester, nylon and acetate, a light green yellow.

It imparts a light green-yellow to poly(methyl methacrylate) lacquer in 0.125% conc. which fluoresces bluish white under UV light. When applied over black, a slightly bluish case is apparent.

EXAMPLE 17 Disperse dyeing procedure A stock dye solution prepared by dissolving 175 mg. dye in 20 to cc. acetone. This is added to a solution prepared by mixing 7 cc. 5% sodium lauryl sulfate solution in cc. water at F. The volume is brought to 350 cc. volume with water at 100 to 120 F.

A 50 cc. portion of the above dye stock solution is added to cc. water. In the case of dyeing polyesters, a carrier is used in the dyebath. The amount of carrier used is 3 ml. of a 50% methyl salicylate aqueous emul- 510m.

A S-gram skein of fibers of the type mentioned below is introduced. The dyebath is heated to the temperature indicated and dyed for one hour at that temperature. It is removed and rinsed. Two of the types are scoured after dyeing, polyester and modified polypropylene. Scouring is done for 10 minutes at the boil in 0.1% neutral soap solution followed by rinsing. The skeins are dried.

The same procedure may be followed with S-gram pieces of fabric instead of yarn or skeins.

12 Fibers dyed At F. Polyester (polyethylene terphthalate) 212 Nylon 66 carpet yarn 205 Acetate (cellulose acetate) 205 Polypropylene, modified with an amine or amide 212 Polyacrylonitrile, modified with an amine or amide 212 A 0.5% shade of dye 0n the weight of the yarn or fabric is obtained by this procedure. This is the depth 5 wherein both Xs are the same and represent either fluoro or acetoxy and R represents methyl, phenyl or acetylaminophenyl.

2. A 1,3,2-oxazaborinide of the formula wherein both Xs represent acetoxy.

References Cited UNITED STATES PATENTS 11/1971 Padmanathan 260256.4 E

ALEX MAZEL, Primary Examiner 50 R. V. RUSH, Assistant Examiner X-ref. Has Been Done in Issued Parent. N0 X-ref. is Necessary Herein. 

